UPDATE 1-Genmab gets positive results from Arzerra trial

* Positive top-line results from cancer drug phase II study

* Says it shows potential for treatment of front line NHL

* Positive results just nine days after drug disappointed

By Teis Jensen

COPENHAGEN, Aug 26 (Reuters) - The Danish biotech company Genmab (GEN.CO) said on Wednesday that it got positive top-line results from a phase II study of its Arzerra cancer drug, which is being co-developed with GlaxoSmithKline (GSK.L).

The news came just nine days after disappointing clinical results with the same drug sent shares in Genmab tumbling more than 30 percent the following day.[ID:nLI58201]

"We are pleased with the positive results shown in this study and believe they are indicative of the potential of ofatumumab (Arzerra) in the treatment of front line follicular non-Hodgkin's lymphoma," Chief Executive Lisa Drakeman said in a stock exchange announcement on Wednesday.

Genmab got the positive results with Arzerra in combination with cyclophosphamide, doxorubicin, vincristine and prednisone (CHOP) in patients with previously untreated follicular non-Hodgkin's lymphoma (NHL).

58 patients were treated in the study and the overall response rate in patients treated with 500 mg of ofatumumab was 90 percent, and for patients treated with 1,000 mg the response rate was 100 percent.

There were no unexpected safety findings reported during treatment and within 30 days after the last infusion, the company said.

The disappointing trial results announced last week showed the top 1,000 milligram dose of Arzerra in patients with NHL who did not respond to the established drug Rituxan produced an overall response rate of just 10 percent -- well below expectations. (Editing by Rupert Winchester)